<!DOCTYPE html>
<html>

<head>
	<meta charset="utf-8">
	<title>菜鸟教程(runoob.com)</title>
</head>

<body>

	<script>
		function changeImage() {
			element = document.getElementById('myimage')
			if (element.src.match("bulbon")) {
				element.src = "pic_bulboff.gif";
			}
			else {
				element.src = "pic_bulbon.gif";
			}
		}
	</script>
	<img id="myimage" onclick="changeImage()" src="pic_bulboff.gif" width="100" height="180">
	<p>点击灯泡就可以打开或关闭这盏灯</p>

</body>

</html>